Greetings all. I fear my understanding of steam operation might be lacking a tad. I am scratching the old head regarding the MPD at Swanage. Alongside the coal dock and water tower is a loco pit between the rails. Whenever I am there it seems relatively clean, but I gather ash and coals were dumped in here by locos.

Although it is hard to see, there also seems to be a pit in the loco shed. Would this serve a different purpose? (i.e. loco repairs and service) - Does the MPD in fact thus have two pits?

I'm curious as to what prototypical practice might have been, as preservation lines operate a little differently.

I think that to some extent, the use of the pits at a depot depended on its size, although I imagine that ashing out would only be done over an outside pit. Oiling up can be done inside or out doors whereas maintenance would preferably be done indoors unless the loco could not be moved inside.At larger depots, there were often dedicated disposal and preparation areas. In later days (1930's on?) larger depots might be equipped with mechanical ash handling plant to avoid the drudgery of shoveling the ash and clinker up out of the pit and then again into a wagon - see Barrow Road, for instance.I stand to be corrected!Dave.

FWIW, to corroborate other comments, on both Welsh narrow gauge steam railways where I volunteer the ash and general filth is kept outside. Locos are towed outside to be lit up and steam raised. Inside is for relatively clean jobs. At the Bala Lake Railway the loco ashpan doors open between the rails so emptying is done over the pit outside. On the WHR the Garratts ashpan doors are on the sides, and there was no pit at Dinas last time I was there. At Porthmadog the pit has room for a wheelbarrow to hopefully catch all the c..p as the fireman spoons it out. At Dinas he has to shovel it up from the concrete apron onto a wheelbarrow. and in both cases take it to the ashpile. At Bala the ash is used to fill holes in the car park or lay a base for the next new siding. Quite a lot of emphasis on both railways on keeping the place clean - not sure, before the days people did this for 'fun', how much this would have been the case...?!